Gas turbine combustors are typically provided with floating collars or seals to permit relative radial or lateral motion between the combustor and the fuel nozzle while minimizing leakage therebetween. The collar is typically welded to the edge of a fuel nozzle hole defined in the dome end portion of the combustor wall. The collar is subject to wear and heat. Radial cracks occur around the fuel nozzle hole, and floating collar assemblies crack due to the metal being exposed to hot air. One cause of the cracking is that the thermal barrier coating, applied on the inner surface of the combustor wall near the fuel nozzle hole, cannot be brought to the edge of the fuel nozzle hole to protect the metal due to weld contamination. A band of unprotected metal must be left exposed in order to perform the weld and, thus, secure the floating collar to the combustor wall. In addition, the welds are exposed to hot air, which inevitably results in cracking.
Accordingly, there is a need to provide a solution which addresses these and other limitations of the prior art, and in particular, there is a need to reduce the occurrence of cracking on gas turbine combustors.